I am running Bungee to 1.15 and 1.12 servers. The 1.12 servers are Forge. (Mods written fo that version)
I have tried to get them all to connect and 1.15 does just fine.
I finally found this solution to install SpongeForge and set global.conf to “ip_forward”
Every time I start the 1.12 server it changes this setting from true back to false.
Bungee is set to ip_forward so I dont know why its resetting.